2 ships laid down for Abyssinia to provide coastal defence/patrol.
Asmara, Abyssinian Coastal Defence ship laid down 1925
Displacement:
1,911 t light; 2,018 t standard; 2,227 t normal; 2,394 t full load
Dimensions: Length overall / water x beam x draught
241.83 ft / 229.66 ft x 45.93 ft x 11.38 ft (normal load)
73.71 m / 70.00 m x 14.00 m x 3.47 m
Armament:
4 - 8.00" / 203 mm guns (2x2 guns), 276.24lbs / 125.30kg shells, 1925 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, evenly spread
8 - 1.46" / 37.0 mm guns (4x2 guns), 1.55lbs / 0.70kg shells, 1925 Model
Quick firing guns in deck mounts
on side, all amidships
Weight of broadside 1,117 lbs / 507 kg
Shells per gun, main battery: 100
4 - 17.7" / 450 mm above water torpedoes
Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 2.76" / 70 mm 108.86 ft / 33.18 m 8.14 ft / 2.48 m
Ends: 0.79" / 20 mm 120.77 ft / 36.81 m 8.14 ft / 2.48 m
Upper: 0.79" / 20 mm 108.86 ft / 33.18 m 8.01 ft / 2.44 m
Main Belt covers 73 % of normal length
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 3.94" / 100 mm 2.76" / 70 mm 2.76" / 70 mm
3rd: 0.79" / 20 mm - -
- Armour deck: 1.57" / 40 mm, Conning tower: 2.76" / 70 mm
Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 5,800 shp / 4,327 Kw = 18.00 kts
Range 3,000nm at 15.00 kts
Bunker at max displacement = 376 tons
Complement:
161 - 210
Cost:
£0.661 million / $2.645 million
Distribution of weights at normal displacement:
Armament: 130 tons, 5.8 %
Armour: 566 tons, 25.4 %
- Belts: 184 tons, 8.3 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 136 tons, 6.1 %
- Armour Deck: 235 tons, 10.6 %
- Conning Tower: 10 tons, 0.5 %
Machinery: 188 tons, 8.5 %
Hull, fittings & equipment: 1,002 tons, 45.0 %
Fuel, ammunition & stores: 316 tons, 14.2 %
Miscellaneous weights: 25 tons, 1.1 %
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
3,982 lbs / 1,806 Kg = 15.6 x 8.0 " / 203 mm shells or 1.3 torpedoes
Stability (Unstable if below 1.00): 1.15
Metacentric height 2.0 ft / 0.6 m
Roll period: 13.5 seconds
Steadiness - As gun platform (Average = 50 %): 49 %
- Recoil effect (Restricted arc if above 1.00): 0.65
Seaboat quality (Average = 1.00): 1.01
Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.649
Length to Beam Ratio: 5.00 : 1
'Natural speed' for length: 15.15 kts
Power going to wave formation at top speed: 62 %
Trim (Max stability = 0, Max steadiness = 100): 48
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 6.56 ft / 2.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 15.42 ft / 4.70 m
- Forecastle (26 %): 13.78 ft / 4.20 m
- Mid (50 %): 13.78 ft / 4.20 m
- Quarterdeck (26 %): 13.78 ft / 4.20 m
- Stern: 13.78 ft / 4.20 m
- Average freeboard: 13.95 ft / 4.25 m
Ship tends to be wet forward
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 72.9 %
- Above water (accommodation/working, high = better): 107.1 %
Waterplane Area: 8,073 Square feet or 750 Square metres
Displacement factor (Displacement / loading): 111 %
Structure weight / hull surface area: 87 lbs/sq ft or 425 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.87
- Longitudinal: 3.85
- Overall: 1.01
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is adequate